[HBASE-25790] NamedQueue 'BalancerRejection' for recent history of balancer skipping

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0-alpha-1, 2.5.0, 2.4.3
• Component/s: Balancer, master
• Hadoop Flags: Reviewed
• Assignee: Zhuoyue Huang
• Reporter: Zhuoyue Huang
• Created: 19/Apr/21 10:34
• Updated: 14/May/21 09:55
• Resolved: 08/May/21 19:13

Description

HBASE-24528 implements a NamedQueue that saved recent history of balancer decision details. Since we want to know exactly why the balancer is skipping to run, we need a new namedQueue called 'BalancerRejection' to hold the history of all details information why the balancer was rejected to run(skipping). LogEntry of 'BalancerRejection' should contain the information below:

1. Reason, to show why this time balancer was rejected

Maybe look like:

 

(cost1*multiplier1+cost2*multiplier2+...+costn*multipliern)/sumMultiplier=0.025 <= minCostNeedBalance(0.35)

2. Detail cost factors and multipliers

Maybe look like:

org.apache.hadoop.hbase.master.balancer.StochasticLoadBalancer$RegionCountSkewCostFunction cost:0.0 multiplier:500.0

org.apache.hadoop.hbase.master.balancer.StochasticLoadBalancer$MoveCostFunction cost:0.0 multiplier:7.0

org.apache.hadoop.hbase.master.balancer.StochasticLoadBalancer$RackLocalityCostFunction cost:1.0 multiplier:15.0

 

Issue Links

• links to: GitHub Pull Request #3182
• links to: GitHub Pull Request #3245